UV Disinfection Stations Raise the Bar

If the pandemic has taught us anything, it is the increased awareness of maintaining proper hand hygiene. According to the Center for Disease Control (CDC) web site, “Regular handwashing is one of the best ways to remove germs, avoid getting sick, and prevent the spread of germs to others.” This begins, of course, with regularly washing one’s hands 5 or more times throughout the day for at least 20 seconds using soap and water. The CDC also recommends the use of hand sanitizer when handwashing is not an option, which is why during the pandemic a hand sanitizer dispenser could be found at the entrance of just about every business, public venue, or restroom.

But do these hygiene efforts go far enough? It turns out the gaping hole in the equation is the cleaning and disinfection of the myriad of personal items we handle with our hands every day.

At the top of the list are our mobile phones, tablets, and other smart devices. According to various studies, individuals check their phones approximately 150 times each day, but the number of times they touch their phone is estimated to be in the thousands. If cell phones are presumed to be relatively clean compared to your hands, consider that scientists at the University of Arizona found cell phones carry 10 times more bacteria than most toilet seats.

In fact, we handle our mobile devices so often they should be considered an extension of our own hands. If the items are dirty, so are our hands – and vice versa. So, when published health advice recommends cleaning smart devices “at least once a day,” it seems woefully insufficient. In addition, wipes, sprays, and cleaning solutions that are abrasive or contain bleach can damage phones, cases, and protective coatings.

Other personal items we regularly handle with our hands include face masks, ID badges, baseball caps, sunglasses, keys, wallets, and jewelry. Many of these items pass through other people’s hands as well, including credit cards, business cards, pens, bills, and coins. Even on the job, workers are increasingly using shared tablets, VR headsets, and even Personal Protective Equipment (PPE) like safety glasses and gloves.

Given the risks, disinfecting our personal items and accessories should be an ongoing health mandate. For those that feel the COVID19 pandemic is over, what if there is a resurgence? A new more transmissible variant? Some other new viruses? What about the other pathogens we already know about? What about protecting those already at-risk prior to the pandemic due to pre-existing conditions?

One solution that warrants closer scrutiny is the use of ultraviolet (UV) light devices. These devices utilize short-wavelength ultraviolet C (UV–C) light to inactivate pathogens including viruses (such as SARS-CoV-2), bacteria, mold spores, and yeast.

UV-C light works by interfering with the nucleic acids of bacteria and other microbes to prevent reproduction and effectively destroy them. UV light has the advantages of being effective, low cost, chemical-free, and in most cases presents no risk to the items being disinfected.

UV-C light irradiation is already a proven technology, verified in many studies and utilized prior to the pandemic in both commercial and residential settings. In large hospital settings, UV light air purifiers are installed to decontaminate surgical equipment/tools and reduce the transmission of pathogens. Hospital-grade UV light machines are also widely used to disinfect patient rooms and operating areas.

To be clear, there are already many UV light devices on the market. However, the main barrier to adoption and perhaps the primary reason these devices are not as ubiquitous as hand sanitizer stations are inherent limitations in design.

Many require direct contact and manipulation to operate the appliance, and there can be questions about the intensity and contact time of the applied UV light. If the item is treated in a static manner, for example placed in an enclosure without being rotated or moved, it is like tanning on the beach on only one side. The UV-C light may not reach all the relevant surfaces.

UV light sources can vary in intensity and output, and there can be line-of-sight issues as well. You have to make sure the UV light is directed at the items from many angles with uniform intensity, and all this requires a high level of engineering.

Many UV disinfection appliances are also essentially designed like microwave ovens. To disinfect an object, the door must be opened, the item added, the door closed, and push buttons used to initiate the cleaning process. The door then must be re-opened to remove the item.

When you are opening and closing the door it can be detrimental to how effective the appliance will be. One reason is the UV lamps do not instantly reach their maximum power and there is a long warm-up time. So, if you turn it off to open the door, you either have to wait until the lamp reaches full power or live with a less efficient and less well determined exposure time.

However, if you place an item on a platform without having to open or close a door, and that continuously rotates in a 360-degree arc through the chamber for about ten seconds, UV-C can be directed in a way that ensures it will hit the targeted surface. By controlling the internal environment and the time within the chamber very precisely, 99.9% of the pathogens on the surfaces of the item can be killed.

By using enclosed, no-contact features, the user is never exposed to UV light and does not have to touch any part of the appliance or push any buttons to initiate the process. This design feature eliminates the potential for cross contamination along with the need for constant maintenance and cleaning as is the case with toilet seats.

For those concerned, UV-C light has been proven to be safe for use on most materials. Nylon, cotton, leather, polypropylene, or plastics are not going to be adversely affected by these types of doses. But the dosages of UV light are high enough to kill germs, bacteria, and viruses, including SARS-CoV-2 (COVID-19).

Self-service disinfection stations like this could be installed in front of entries/exits or bathrooms at public venues, retail stores, healthcare facilities, academic institutions, airport terminals, and nursing homes – to name a few. In the workplace, facility management companies or major corporations could install the appliance to protect workers as part of corporate safety initiatives.

Although at the time the primary driver to develop this technology was COVID-19, this shouldn’t be viewed as just a COVID-related product. It is an approach that could have a lasting impact on hygiene now and in the future using a technology [UV-C] that has been around long before the pandemic.

Robert Tegel is President of Tebots, Inc., which specializes in the manufacturing and assembly of industrial appliances.